New prospects in the diagnosis and treatment of immune-mediated inner ear disease

Audiovestibular Dysfunction in Patients with Hashimoto's Disease: A Systematic Review

Although the inner ear is considered an immune-privileged organ because of the blood-labyrinth barrier, accumulating evidence has revealed an unexpected relation between Hashimoto's disease and inner ear damage manifesting as audiovestibular dysfunction. Hashimoto's disease can simultaneously affect both the auditory and vestibular systems, either through direct autoantibody attacks or through metabolic dysfunction associated with hypothyroidism. Currently, there is no consensus regarding tests or treatments for audiovestibular dysfunction related to Hashimoto's disease. In this review, we summarize the currently available evidence regarding the characteristics, pathophysiology, diagnostic approaches, and treatment of audiovestibular dysfunction in patients with Hashimoto's disease. Furthermore, we propose a specific steroid-plus-thyroxine treatment protocol to manage audiovestibular dysfunction associated with Hashimoto's disease. This condition may respond to adequate treatment, potentially allowing reversibility if it is recognized and managed in a timely manner. Conversely, delayed diagnosis or failure to recognize the subtle presentation of audiovestibular dysfunction in patients with Hashimoto's disease may lead to progressive hearing loss, immobility, and reduced quality of life. Based on the updated evidence in our review and our modified treatment protocol, we aim to provide new insights and therapeutic directions for clinicians managing audiovestibular dysfunction in patients with Hashimoto's disease. Trial registration: PROSPERO CRD420250652982.

Prevalence and Intriguing Clinical Profiles of Autoimmune Inner Ear Diseases in Sudden Sensorineural Hearing Loss

INTRODUCTION

Sudden sensorineural hearing loss (SSNHL) is idiopathic in 70-90% of cases with 10-30% linked to vascular injuries, viral infections, or autoimmune inner ear disease (AIED). AIED contributes to less than 1% of all hearing losses, categorized into primary, affecting only the inner ear, and secondary, associated with systemic autoimmune diseases (SAID). This study examines the prevalence and features of AIED in SSNHL in a tertiary referral center.

MATERIALS AND METHODS

We conducted a prospective study from November 2021 to December 2022 including SSNHL patients who exhibited symptoms like hearing loss or tinnitus. Evaluations included tympanometry, pure tone audiometry, and blood tests, with suspected AIED cases further assessed by rheumatologists using Lobo's diagnostic criteria. Treatment responses were monitored through regular audiometry updates.

RESULTS

Out of 694 SSNHL patients, 43 (6.2%) were diagnosed with AIED, of which 36 (83.7%) had primary AIED and 7 (16.3%) had secondary AIED linked to conditions like Sjögren's syndrome and systemic lupus erythematosus. Treatment response was seen in 19.4% of primary and 42.9% of secondary AIED cases.

CONCLUSION

The prevalence of AIED in SSNHL patients was found to be 6.2%, with a notable fraction also suffering from SAID. Responses to treatment were positive in about a third of these cases, highlighting the importance of interdisciplinary management for this rare yet significant cause of SSNHL.

Investigating the Process of Autoimmune Inner Ear Disease: Unveiling the Intricacies of Pathogenesis and Therapeutic Strategies

Autoimmune inner ear disease (AIED) is a rare condition characterized by immune-mediated damage to the inner ear, leading to progressive sensorineural hearing loss (SNHL) and vestibular symptoms such as vertigo and tinnitus. This study investigates the pathogenesis and therapeutic strategies for AIED through the analysis of three cases with different underlying autoimmune disorders: rheumatoid arthritis, relapsing polychondritis, and IgG4-related disease. The etiology of AIED involves complex immunopathological mechanisms, including molecular mimicry and the "bystander effect," with specific autoantibodies, such as those against heat shock protein 70 (HSP70), playing a potential role in cochlear damage. Diagnosis remains challenging due to nonspecific symptoms and the lack of distinct biomarkers, emphasizing the need for comprehensive clinical evaluation and exclusion of other hearing loss causes. Treatment primarily involves immunosuppressive therapies, with glucocorticoids as the first line, effective in 70% of cases. However, resistance or partial response necessitates the use of additional agents like methotrexate and biologics such as anti-TNF and IL-6 receptor antagonists. Early intervention is crucial for favorable outcomes, as demonstrated in the studied cases, where timely corticosteroid and immunosuppressive treatments led to significant hearing improvement. The study underscores the importance of personalized treatment strategies based on individual immunologic profiles and comorbidities. Our findings highlight the heterogeneity of AIED and the potential for biologic therapies in refractory cases.

Prevalence of hearing loss, tinnitus, vertigo and sudden deafness among patients with polymyositis and dermatomyositis

Little is known about a possible association of autoimmune inner ear disease among patients diagnosed with polymyositis (PM)/dermatomyositis (DM). This study aimed to explore differences in the prevalence of inner ear symptoms among patients with and without PM/DM using a nationwide population-based dataset. Data for this study were retrieved from the Taiwan National Health Insurance Research Database. The study sample included 1622 patients diagnosed with PM/DM and 8109 propensity-score matched comparison patients without PM/DM. We performed multivariate logistic regressions to calculate odds ratios (ORs) and 95% confidence interval (CI) for tinnitus, hearing loss, sudden deafness, and vertigo among patients with PM/DM versus comparison patients. Chi-square tests showed statistically significant differences between patients with PM/DM and comparison patients in the prevalence of tinnitus (16.1% vs. 12.7%, p < 0.001), non-conductive hearing loss (9.2% vs. 6.8%, p < 0.001), and vertigo (14.4% vs. 11.1%, p < 0.001). The adjusted ORs for tinnitus, non-conductive hearing loss, and vertigo, respectively, were 1.332 (95% CI = 1.147-1.547), 1.399 (95% CI = 1.154-1.696), and 1.374 (95% CI = 1.173-1.611) for patients with PM/DM when compared to comparison patients. Our study finds that patients with PM/DM have higher prevalence rates of tinnitus, non-conductive hearing loss, and vertigo than comparison patients.

Bibliometric and altmetric analysis of research relating to antiphospholipid syndrome based on VOS viewer (2011-2021)

BACKGROUND

Antiphospholipid syndrome is an autoimmune disorder characterized by recurrent vascular thrombosis and pregnancy losses in the presence of persistently positive antiphospholipid antibodies. Bibliometric analysis and altmetric analysis are methods of analyzing academic productivity and influence. Currently, the assessment of antiphospholipid syndrome through the above analyses is lacking. This study investigated the quantity and quality of studies in the field of antiphospholipid syndrome and revealed the characteristics of worldwide productivity on this disease by the bibliometric analysis and altmetric analysis.

METHODS

The terms "APS," "antiphospholipid syndrome," "antiphospholipid-antibody syndrome," and "Hughes syndrome" were searched on the Web of Science Core Collection from January 1, 2011, to December 31, 2021. Original articles and reviews were selected. We set the filters as "English."

RESULTS AND CONCLUSION

A total of 1818 articles were retrieved from 68 countries, of which 20 met the criteria of major active countries. High-income countries contributed 1341 articles (73.48%). The number of articles annually increased significantly in the 10-year period (P < 0.001). The USA (253, 13.91%) was the most productive country. Adjusted by population, Serbia was top of the list. According to the gross domestic product analysis, Serbia ranked first. The most used keywords such as thrombosis and antiphospholipid antibodies were presented by keywords analyses. A content analysis found antithrombotic and anticoagulant therapy as research hotspots. A significant correlation was detected between average citations and altmetric attention scores (P = 0.002) and Mendeley readers count (P < 0.001). From 2011 to 2021, the number of global articles increased rapidly. Most papers came from high-income countries. The relationship between the bibliometric and altmetric analyses were basically consistent; therefore the two can prove/complement each other. Key points • We revealed the global productivity characteristics of the papers related to antiphospholipid syndrome by using the methods of bibliometric analysis and altmetric analysis. • We found the most selected articles that describe the treatment of antiphospholipid syndrome, especially antithrombotic and anticoagulant treatments, which may be the current research hotspot.

Fused deposition modelling 3D printing proof-of-concept study for personalised inner ear therapy

OBJECTIVES

There is a requirement within ear therapeutics for a delivery system capable of safely delivering controlled doses to the inner ear. However, the anatomy and sensitivity of the inner ear make current delivery systems problematic and often ineffective. Therefore, a new delivery system is required to overcome these issues and provide a more efficacious system in the treatment of inner ear disease. This study assesses the potential of 3D printing (3DP) as a fabrication method for an implantable drug delivery system (DDS) to the inner ear.

KEY FINDINGS

Three implantable designs of varying geometry were produced with fused deposition modelling (FDM) 3DP, each loaded with 0.25%, 0.5% and 1% levofloxacin; filaments prepared by hot-melt extrusion. Each implant was effective in providing sustained, therapeutic release of levofloxacin for at least 4 days and as such would be effective in therapeutic treatment of many common inner ear diseases, such as otitis media or Ménière's disease.

CONCLUSIONS

This proof-of-concept research was successful in utilising FDM as a fabrication method for a DDS capable of providing prolonged release directly to the inner ear and highlights the viability of 3DP in the fabrication of an inner ear DDS.

Autoimmune Inner Ear Disease among Patients with Selective IgA Deficiency

OBJECTIVES

Autoimmune inner ear disease (AIED) is a distinct clinical entity from sudden sensorineural hearing loss. The purpose of this study was to investigate the clinical characteristics of AIED in patients with selective IgA deficiency (sIgAD).

MATERIALS AND METHODS

This retrospective observational study was based on data from the Leumit Healthcare Services database in Israel. We searched all subjects aged ≥12 years who had undergone serum total IgA measurements during 2004-2014 for any reason. The sIgAD patients included all subjects with serum IgA of ≤7 mg/dL (0.07 g/L). A control group was randomly sampled from the full study population (n ≈ 730,000) with a case-control ratio of 10 controls for each case (1:10).

RESULTS

Among 347 subjects with sIgAD, we identified 9 patients with concomitant AIED (sIgAD + AIED group). This group was characterized by a higher prevalence of allergic diseases (8 patients; 88.9%) than sIgAD patients without AEID (sIgAD + AIED group; 153 patients; 45.2%; p = 0.014). Both systemic diseases (3 patients; 33.3%) and organ-specific autoimmune diseases (7 patients; 77.8%) were more prevalent in the sIgAD + AIED group (sIgAD + AIED group: 19 patients 5.5%, p = 0.015; sIgAD - AEID group: 76 patients, 21.9%, p < 0.001), with an OR of 8.39 (1.94-36.19; p = 0.004). sIgAD patients with and without AIED were characterized by a higher prevalence of documented episodes of acute otitis media, allergic diseases, and autoimmune diseases than the control group.

CONCLUSION

The study exposes a significant association between AIED and sIgAD. We believe that sIgAD has to be excluded in AIED patients.

Middle-ear dexamethasone delivery via ultrasound microbubbles attenuates noise-induced hearing loss

OBJECTIVES/HYPOTHESIS

In this study, we expanded our previous investigation by testing the efficiency of trans-round window membrane dexamethasone (DEX) delivery mediated by ultrasound (US)-aided microbubbles (MBs) and its preventive effects regarding noise exposure in animal models.

STUDY DESIGN

Live animal model.

METHODS

Forty-two pigmented male guinea pigs were divided into the following three groups: an US-MBs (USM) group, in which the tympanic bulla was filled with DEX and MBs and exposed to US; a round window soaking (RWS) group, without the US irradiation; and a control group. The above-mentioned manipulations were performed 2 hours prior to white noise exposure. The cochlear damage, including auditory threshold shifts, hair cell loss, and expression of cochlear HMGB1, was evaluated.

RESULTS

The enhanced DEX delivery efficiency of the USM group was approximately 2.4× to 11.2× greater than that of the RWS group. After the noise exposure, the RWS group showed significant cochlear protection compared with the control group, and more significant and dominant protective effects were demonstrated in the USM group.

CONCLUSIONS

The application of US-MBs provides a safe and more effective approach than spontaneous diffusion, which is commonly used in clinical practice; thus, this technique holds potential for future inner-ear drug delivery.

LEVEL OF EVIDENCE

NA Laryngoscope, 129:1907-1914, 2019.

l-Thyroxine does not prevent immunemediated sensorineural hearing loss in autoimmune thyroid diseases

OBJECTIVE

This is the first report dealing with immune-mediated inner ear disease (IMIED) hearing loss in a group of patients affected with autoimmune thyroid disease (AITD), whose treatment required corticosteroids, despite being treated with levothyroxine. Immunopathology linking the inner ear and the thyroid gland is also presented.

PATIENTS

A total of 220 patients were selected with sensorineural hearing loss (SNHL) of causes other than presbycusis. Audiometry was performed and pure tone average was calculated before and after treatment with corticosteroids.

RESULTS

Eighty-four (84) patients had SNHL of autoimmune origin, and 15 patients were diagnosed with AITD (Hashimoto's disease). Bilateral hearing loss was observed in 10 patients (66.5%). Sudden sensorineural hearing loss was the most frequent clinical form of presentation. Nine patients showed a hearing recovery greater than 10dB after corticosteroid treatment.

CONCLUSIONS

Acquired hypothyroidism is thought to affect hearing due to different mechanisms. Although specific hormonal therapy may improve peripheral or central auditory disorders associated with hypothyroidism, the presence of IMIED in AITD patients requires another approach. Altered immune regulatory mechanisms involving Treg cells and CD4+CD45RO cells have been suggested in patients with AITD and IMIED. In the present study, although all the patients with hypothyroidism and subclinical hypothyroidism were being treated with levothyroxine, immune-mediated hearing loss was observed. Therapy with corticosteroids could achieve hearing recovery. Since inner ear and thyroid gland share possible antigen targets, we highlight the existence of IMIED in AITD patients and the importance of implementing appropriate therapy with corticosteroids.

Ear Involvement in Inflammatory Bowel Disease: A Review of the Literature

Inflammatory bowel disease (IBD) is a multisystemic disease. The ear is a rare but recognized site of extraintestinal manifestations of IBD. In external ear, the more common manifestations of IBD are pyoderma gangrenosum, metastatic Crohn’s disease and relapsing polychondritis and the treatment includes corticosteroids and anti-TNF agents. Sensorineural hearing loss (SNHL) is the most common ear disease in IBD and especially in patients with ulcerative colitis. In most cases of IBD patients with SNHL, the hearing loss is attributable to autoimmune inner ear disease (AIED). Diagnosis of AIED is based on clinical presentation, the demonstration of a progressive sensorineural hearing loss in periodic audiological tests, a response to immunosuppressive drugs and exclusion of other causes of SNHL. The only diagnostic test that is available for clinical use is the Otoblot test (Western blot for antibodies against 68 kD protein-inner ear antigens). Initial therapy is usually steroids, with a step up to anti-TNF-a therapy and cochlear implantations with failure of treatment. Furthermore, Cogan’s syndrome, a chronic disease characterized by deafness, vertigo keratitis and aortitis, has been associated with IBD and mainly with Crohn’s disease.

Otologic disorders causing dizziness, including surgery for vestibular disorders

This chapter will focus on vertigo/dizziness due to inner-ear malformations, labyrinthine fistula, otosclerosis, infectious processes, and autoimmune inner-ear disorders. Inner-ear malformation due to dehiscence of the superior semicircular canal is the most recently described inner-ear malformation. Vertigo/dizziness is typically induced by sound and pressure stimuli and can be associated with auditory symptoms (conductive or mixed hearing loss). Labyrinthine fistula, except after surgery for otosclerosis, in the context of trauma or chronic otitis media with cholesteatoma, still remains a challenging disorder due to multiple uncertainties regarding diagnostic and management strategies. Otosclerosis typically manifests with auditory symptoms and conductive or mixed hearing loss on audiometry. Vertigo/dizziness is rare in nonoperated otosclerosis and should draw clinical attention to an inner-ear malformation. Computed tomography scan confirms otosclerosis in most cases and should rule out an inner-ear malformation, avoiding needless middle-ear surgical exploration. Labyrinth involvement after an infectious process is unilateral when it complicates a middle-ear infection but can be bilateral after meningitis. Labyrinth involvement due to an inflammatory disease is a challenging issue, particularly when restricted to the inner ear. The diagnosis relies on the bilateral and rapid aggravation of audiovestibular symptoms that will not respond to conventional therapy but to immunosuppressive drugs.